Paged i2c accessor

[FoamyGuy]

Paged I2C accessor that supports chips like CS42L42 which use a page register to be able to re-use the same smaller address space across different pages.

[tannewt]

Are there other chips that need this? Could it live with the CS42L42 for now until it is needed elsewhere?

[FoamyGuy]

There are other chips that use the same paging mechanism. TLV320AIC3xxx, LSM6DSO/DSOX/DSV, LSM6DSR, LIS2DUX, other Cirrus codecs, even BNO055 which we have a driver for but it doesn't use adafruit_register.

So it is used more broadly, but I wouldn't say it's strictly needed anywhere else at this time. Can move it into the CS42L42 driver for now.

[tannewt]

How do those other drivers do it? Should we refactor them all?

[FoamyGuy]

@tannewt I think the only with an Adafruit driver is the BNO055. It doesn't use adafruit_register. It has it's on _write_register() function which it just calls "manually" to write the page ID before other transactions, like here: https://github.com/adafruit/Adafruit_CircuitPython_BNO055/blob/33fec1851ce0fd660e210a024365461b11ec0bf0/adafruit_bno055.py#L510. I do prefer the adafruit_register style drivers, so I'd be in favor of this getting refactored to use adafruit_register, and if that were to happen it would need some solution for the paged access.

The TLV320AIC3204 has a community bundle driver. That one uses adafruit_register with PagedRWBit/Bits classes that are in the driver itself https://github.com/relic-se/CircuitPython_TLV320AIC3204/blob/accbf7ae8f8a649aeb7dce07d62a1a291ef23e89/relic_tlv320aic3204.py#L398-L443

[tannewt]

Ok, I've reopened this so drivers can be migrated to it.

[tannewt]

One suggestion to make a new file for it. Otherwise it'll be good. I like packing the page number into the register address.

[tannewt]

Put this in a new file so it is imported separately.